This 4-year prospective, longitudinal study is designed to explore factors that enhance or impede the initial and sustained use of the female condom for HIV/STI prevention. The study targets high-risk urban women in Hartford, CT, who are primarily African American and Puerto Rican, including drug users, sex workers, non-drug using women with multiple or drug-using sex partners, as well as a small number of high-risk men. The study aims are: 1) to examine factors affecting initial and sustained use of the female condom for HIV/STI prevention among high-risk women and their male sex partners after reducing initial barriers associated with lack of information and accessibility; and 2) to examine conditions affecting female condom adoption associated with personal network and sexual relationship factors of high-risk women and men overtime. The study includes two primary components that together allow the integration of qualitative and quantitative methods to assess sustained female condom use in the target population. One component is a quantitative cohort study of 500 high-risk women who will participate in a prospective, longitudinal survey measuring demographic, epidemiological (HIV risk and prevention), psycho-social (attitudinal, personal agency), sexual relationship (partner, gender), and social network/peer influence factors conducted at 3 time points (intake, 1-month and 10-months). The cohort study is designed to assess predictors of initial female condom use with different types of sex partners and factors associated with its sustained use. The second component is a qualitative and quantitative partners' female condom trial with 75 couples (high-risk women and their male primary, casual, and/or paying partners), in which they use the female condom together for one or two consecutive 2-week trials to assess sexual relationship, gender dynamic, and other factors affecting their use of female condoms, with post-trial and 10-month follow-up interviews to assess their sustained use of the female condom with this and other partners over time. Qualitative and quantitative data will be used to test hypotheses regarding factors affecting sustained female condom use and to assess the process and dynamics of female:, condom adoption in the study population. Concurrent implementation of the two study components and a sampling design that will create equivalent samples in both components support the integrated analysis of qualitative and quantitative data to enhance our interpretation of project findings.